Method and apparatus for controlling a safety-critical process
AssigneePilz GmbH & Co. KG
InventorDietmar Seizinger
Life of this patent
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Abstract
The invention relates to a method and an apparatus for controlling safety-critical processes, such as the monitoring of protective doors, emergency stop switches, light curtains and the like. A control unit is connected to a plurality of I/O units via a data transmission link. The I/O units transmit process data to the control unit, with the process data being protected against transmission errors by means of a diversitary multiple transmission. The process data are encoded using a variable keyword in order to generate variably encoded process data. The variably encoded process data are transmitted to the control unit as part of the diversitary multiple transmission.
Claims24
A method for controlling a safety-critical process, comprising the steps of:
- providing a control unit for processing safety-critical process data relating to the operational state of a remote safety-critical sensor device and/or a remote safety-critical actuator device,
- providing at least one I/O unit that is connected to the safety-critical sensor device or to the safety-critical actuator device for monitoring the safety-critical sensor device or monitoring and activating the safety-critical actuator device, respectively,
- providing a data transmission link for connecting the control unit and the at least one I/O unit,
- encoding the safety-critical process data using a variable encoding algorithm in order to generate variably encoded safety-critical process data, such that said variably encoded safety-critical process data repeatedly changes even when there is no change in the safety-critical process data, and
- transmitting the variably encoded safety-critical process data from the I/O unit to the control unit via said data transmission link.
A method for controlling a safety-critical process, comprising the steps of:
- providing a control unit for processing safety-critical process data relating to the operational state of a remote safety-critical sensor device and/or a remote safety-critical actuator device,
- providing an I/O unit connected to the control unit via a data transmission link and to the safety-critical sensor or to the safety-critical actuator device for monitoring the safety-critical sensor device or monitoring and activating the safety-critical actuator device, respectively, and
- transmitting the safety-critical process data from the I/O unit to the control unit, with the safety-critical process data being protected by means of a diversitary multiple transmission,
- wherein the safety-critical process data are encoded using a variable encoding algorithm in order to generate variably encoded safety-critical process data, and wherein the variably encoded safety-critical process data are transmitted to the control unit as part of the diversitary multiple transmission.
A safety-critical process control apparatus, comprising:
- a control unit for processing safety-critical process data relating to the operational state of a remote safety-critical sensor device and/or a remote safety-critical actuator device,
- at least one I/O unit that is connected to the safety-critical sensor device or to the safety-critical actuator device or monitoring the safety-critical sensor device or monitoring and activating the safety-critical actuator device, respectively, and
- a data transmission link for connecting the at least one I/O unit to the control unit,
- the at least one I/O unit generating the safety-critical process data from a signal input received from the device to which it is connected and encoding the safety-critical process data using a variable encoding algorithm in order to generate variably encoded safety-critical process data, such that said variably encoded safety-critical process data repeatedly changes even when there is no change in the safety-critical process data, and
- the at least one I/O unit being designed to transmit the variably encoded safety-critical process data to the control unit by means of a diversitary multiple data transmission via the data transmission link.
Dependencies are inferred from the claim text.